Above is another version of the quick-hitch coupler for the Kubota KX-161 and U-45 mini excavator.  Click here for a list on quick-hitch adapters for other makes.

This design is for a hanger, if you are looking for a rigid mount for demolition use, click here.

Hook up to the bucket curl cylinder and to the thumb circuits.

The  grapple can be hooked to the bucket curl cylinder hydraulic outlets for opening and closing the grapple and to the thumb cylinder outlets for the rotation.  Choose quick-hitch coupler that has a "heel" which rests on the boom. To make switches easier, the operator might choose to equip the excavator and the hoses to the grapple with hydraulic quick hitch couplers. To facilitate the hydraulic quick couplers, the hoses are equipped with ends  that  have 1/2" NPT thread.

Hookup to one circuit only, dividing the oil flow in two with a diverter solenoid.

Many compact excavators have an auxilary oil flow circuit for the thumb function. One can divide the oil flow for the thumb circuit into two by installing a flow divider. That means that one can both rotate the grapple and open and close it from the same circuit.   The bucket curl is left intact so the switch to and from the grapple is easier. In this case, the operator has a switch in the cab which can send the oil either to the grapple or the rotator. The oil flow is then started by moving the hydraulic lever that engages the circuit. The control box in the cab is hooked to 12V DC and a electric wire runs to the flow divider which is mounted to the quick coupler frame. The wire  has a detach socket and the oil hoses are ready to have hydraulic quick couplers installed.